Relief shown by hachures. From: A new universal atlas. 1852 or 1853 ed. "Entered according to act of Congress, in the year 1850, by Thomas, Cowperthwait & Co. ..." Includes table of steamboat routes. Inset: Western part of Michigan.: Original version published [Philadelphia] : Thomas, Cowperthwait & Co., [1852 or 1853]; Scale [ca. 1:2,050,000]